Selective copolymerization of isobutylene from a c4 mixture



3 merization catalyst.

Patented July 22, 1952 4:

SEIJEGTIVE'GOPOIZYMERIZATIOMOE ISO BUT-YLENE-FRQM-A-CLMIXZEURE Helmuth G. Schneider; Westfielih David W. Young; Roselle, and Hans G. Goering, Eliza? bath; NHL, asisig'nozrsto.Stam'lardQiLDevelop,-v ment Company, a corporation of Delaware No Drawing. Application May 20, 1950, 1 V 7 Serial No. 163,326 .4

, ii-claims I 1 e'lfhisinnention. relates to the copolymerization L i'scbutylene" with a polymerizabie compound (01.. Mill -80H) containing: an aromatic nucleus and more par- (1. Cinzthe presence of an active halideflrp'olyi This process weli described inzU. S; Patent No. 2,274,749: The proe+ ess described in this patent presupposes the use of pure monomers since it is well known in the art that the presence' of other olefins substantially reduces the ,Y molecular Weight of. the, prodnot by virtue or catalystspoisoningge Substantial amounts ofisobutylene are formed'iby; the cracking; of-hydrocarb'on mixtures: and is-zobtainedlin admixture with other four:- carbon hydrocarbons irrzapreliminary distillation. oijthe cracked prod,-

It has been theiusualcustomtaremovethe'iso butylene from this fraction bytdistil'lation',.acid

treatment or other means designed to obtain a "reactedatc. with 261 ms. of styrene in ucts; The; followingfis; an analysis,,oii"a-v typical Client:

1 Per'centbyvol'ume Propylene. y.. 011 Propane" n s .s L6 Isobutane r 35.2 n-Butane 18.3 Isobutylene 15.9 Butene-l 12.2 Trans butene-Z 9.2 Cis. butene-2 6.2;- Butadiene 0.3 C5+ 0.6 Total C4 nlefins 43.5 -Tcta1 sec. olefins; 1 274d practically 100% pure iscbutyl'ene or one 0011- taining no secondary o1efin.. This is often an ex:'

pensive and timeeconsumingirprocess. The present process.mzercomes.theseidisadvans 2. tages of the. prior: art by providing an improved process-ion carrying out the copolymerization;

According; to the present invention, the isobutylene contained in any C4 cut obtained in the cracking ofi hydrocarbons is selectively copo'lye merized-,.Witlr styrene or other polymerizable-or= ganic compound containing an 'aromaticn-ucleus by subjecting the :mixture of the C4 cut and": the polymerizable compound to the action ofacone trolled amount of metal halide'only'slightly'in excessof that' needed to, initiate the reaction. Either solid. catalyst. or catalystv dissolved in a non-polar solvent-may; beu-sed at polymerization temperatures not above +10 C., but as low asf-20--"Gi,;-40 0.; C. or evenxlower: The solvent-"used must be one-which formsne complex withthe aluminum chloride-and whi'ch remains a liquid" at;thefreaction temperature. Suitable solvents 'aretheloweralkyl halides-such as'methylchloride:and: ethyl chloride;- Suitable metal halides include aluminum halides' snch as aluminumchloride or aluminum bromide; titanium-chloride;zirconiumtetrachloride V The invention" will be -more clearly-understood Twc liters of a refinery C4 out containing 181 gms. of isobutylene and 496 gms. total olefins were twobatches; The first batch was polymerized with solid aluminum chloride twhereas-alummum v thistemperatureare. relativelyhard.

TllbIG I-T ormwrme coNm'rioNs 7 i l f Fe d wai hLP ILL c i t i igh P n e g pence iys 2011 I e t: .ercentPol er Cat 1 t Styrene Styrene+total Reaction Yield ym Efli'c i ei iiy L M I oleflns) Bull-4s k I i (on. Styrene (on-Styrene- Ti (on Styrene (on'styrene +IsohutyI- w -totaL --So1id.T Liquid- +-Isobut 1- totaL l ayee ene basis) oleflns basis) (mm') ene) y jl efi'ns) A101) n 59 s4 '1 4.9 -s5 6.8 4K0 1 --2..i. 59- 311' 35 107.0 62.0" 89 PRODUCT EVALUATION (STEAM BTRIPPED AT 200 C.)

Weight Percent Crude (Weight Percent n I I Polymer Yield Crude polymer) Inspections 0f Bottoms (Resin).

Run; St St Iutrinl SitPit on yrene on yrene s c o o n and Isobutyltotal Distillate 3 3x5 Vise. (tolu- (Ball and. 3??? ene) olefins) enesolvent) Ring) 7 O a 1 6.8 4.0 2 107.0 62.0 95 0.049 61 C 1. 0

Table '11 I J Table IV ANALYSIS OF 04 CUT (LIQUID VOLUME PERCENT) ANALYSIS OF C4 CUT (LIQUID VOLUME PERCENT) 1 Spent 0 Cut I V H V p v Spent (14 Cut oomppgnt Feed 7 Componen 7 1. Feed Run #1 Run #2 Run R1111 Run .4 ""if ""153 0.0 0.6 0.4 0.0 .9 41.6 43.3 18.7 22.6 22.0 20.5 .5 12.2 0.0 46.7 55.3 55.7 55.3 .-1 11.7 12.7 v 11.9 0.2 0.7 2.6 .2 r 6.2 10.0 9.2 10.1 10.1 10.3 .7 3.5 V 11.6 3.8 as 3.0 3.9 .4 0.4' 0.2 5.8 0.4 6.1 8.3 1.8 '25 4.7 04 0.2 0.1 0.2 3.5 0.8 1.0 i 0.9 Total 100.0 100.0 100.0

, EXAMPLE 2 -EXAIVIPLE 3 Two liters of a refinery 04' out containing 148 gms. ofisobutylene and 392 gms. of total olefins were reacted under reflux conditions with styrene in'three. batches using solid aluminum chloride asthecatalyst: a diiferent amount of styrene was added to each batch. The temperature was maintained at 0 C. The data are presented in the following tables. Table III shows that high yields of resinand catalyst efficiencies were ob- .tained and Table IV shows that isobutylene is removed selectively from the feed. The resins formed are relatively soft.

Threeadditionalruns were made under the same, conditions as in Example 2' except that the catalyst was aluminumchloride. .dissolve d..in ethyl chloride. When but 0.13% A1C13 was-used run' #6), only a small amount of resin was formed, as shown'by Table V However, Table VI shows that only isobutylene was removed When as 'much as 0.70 and 0.76% AlCh dissolved lnethyl chloride was used, all the .olefiris were copolymerized with the styrene, asshoj'wn in Table V.

Table 'III OPERATING, CONDITIONS from the feed to copolymerize with the styrene i Feed, Weight Per Cent Reaction .Weight Per Cent Polymer I Styrene weight 1 Yield t i v gengCatalysit Run (on Styrene (on Styrene on tyrene (on Styrene I gms. olymer I b, I V +1tg1tla1 ggih fig g g} (on Styrene $1. 3 gmljuoh) so may ene 0 e s min. Y e s 7 basis) basis) I V WM Y I V 40 :20 0.41 120 0 115 58 142 4 27 V 0. 37. I 120, 0 60 162 5.. 60 V 36 0.33 O 97 59 PRODUCT EVALUATION (STEAM STRIPPED AT 200 C.

Wei ht Per Cent Crude (Weight Per Cent on Polymer Yield QrudePolymer) Inspectwn (Resin) Run v Intrinsic Soft. Pt. Penetra- (on Styrene (on Styrene Bottoms V180.

Isbbutylene) Total Ole'fin's) 1315mm '(Resin) (toluene (Ball and p w solvent) Rmg) V 77 115 58 3 97 0.0 V Q 28 too 5011: 110 60 3 97 0.043 '10 18.5 97 59 4 96 U. 0 57 .10. 3

Table V OPERATING CONDITIONS Feed, Weight Percent Reaction Weight Percent Polymer Styrene weight Percent Yield Catalyst Efli- Run v stcatalyitqgognl lris ielncy (gins. yrene o a o ymer gm. g i fgfggfi Oelflns Liquid) Time Tem (OnStyi-ene+ (OnStyrene+ A1013) Y 3 S (min.) 03 Isobutylene) Total 01am) Basis) basis) 59 34 0.13 60 +1 6. s 4. so 79 57 0.10 60 +3 132.6 95. 0 13s 86 so 0. 16 90 +3 123. o 99. o 130 PRODUCT EVALUATIONKSTEAM STRIPPED AT 200C.)

Run Visual Inspection Yield too low. Soil, tacky product. Fairly brittle, but tacky product.

From the above data, it is evident that isobutylene selectively polymerizes from a mixture butene-Z, trans butane-2, and butadiene, the amount of butadiene being not more than 0.4% of the materials other than styrene, to temperatures not above +10 C. in the presence of an amount of aluminum chloride only slightly in excess of that required to initiate the reaction 0 whereby the isobutylene is copolymerized with with other olefins when carrying out the reaction in the presence of solid aluminum chloride. When using AlCIs dissolved in a non-polar solvent, the amount of catalyst added to the C4 cutstyrene reaction mixture must be closely controlled in order to obtain selectively copolymerization of styrene and isobutylene. It larger amounts of liquid catalyst are used, all of the oleflns in the C4 cut tend to polymerize with the styrene.

The nature of the present invention having thus been set forth what is claimed as new and useful and desired to be secured by Letters Patent is:

1. The process of selectively copolymerizing isobutylene from its mixture with other C4 olefins. said mixture containing not more than 0.4% of butadiene, which comprises adding styrene to said mixture of isobutylene and C4 olefms and subjecting the mixture of styrene, isobutylene and other olefins to copolymerization at temperatures not above +10 C. in the presence of an amount of aluminum chloride only slightly in excess of that needed to initiate the reaction.

2. Process according to claim 1 in which the reaction is carried out in the presence of solid aluminum chloride.

3. Process according to claim 1 in which the reaction is carried out in the presence of aluminum chloride dissolved in a non-complex forming non-freezing alkyl halide solvent.

4. The process which comprises subjecting a mixture of styrene, isobutylene, butenc-l, cis

the styrene to the substantial exclusion of the butene-l, butane-2, and butadiene.

5. Process according to claim 4 in which the reaction is carried out in the presence of solid aluminum chloride.

6. Process according to claim 4 in which the reaction is carried out in the presence of aluminum chloride dissolved in a non-complex forming non-freezing alkyl halide solvent.

7. The process of making a resin composed essentially of styrene and isobutylene, which comprises adding styrene to a petroleum C4 fraction containing about 11.9 to 15.9% of isobutylene, about 18.8 to 27.6% of other butenes, not more than about 0.1% propylene, not more than about 0.4% of butadiene, and not more than about 3.5% of C5 hydrocarbons, the balance being butanes, the amount of styrene in said mixture being about 40 to 86% on the basis of the total amount of styrene plus isobutylene, and subjecting the mixture of styrene and C4 fraction to copolymerization at a. temperature of C. to 10 C., in the presence of an amount of aluminum chloride only slightly in excess of that needed to initiate the reaction, the amount of said catalyst being suflicient to cause substantially complete copolymerization of the styrene with the isobutylene, but insuflicient to cause more than a minor proportion of the other butenes to enter into the copolymerization.

8. Process according to claim 7 using as catalyst aluminum chloride dissolved in an alkyl chloride of 1 to 2 carbon atoms, the amount of said aluminum chloride being about 0.66 to 0.76% based on the styrene plus total olefins.

9. Process according to claim 8 carried out at a polymerization temperature of 35 C. to 3 C.

HELMUTH G. SCHNEIDER... DAVID W. YOUNG. HANS G. GOERING.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,438,340 Johnson Mar. 23, 1948 

4. THE PROCESS WHICH COMPRISES SUBJECTING A MIXTURE OF STYRENE, ISOBUTYLENE, BUTENE-1, CIS BUTENE-2, TRANS BUTENE-2, AND BUTADIENE, THE AMOUNT OF BUTADIENE BEING NOT MORE THAN 0.4% OF THE MATERIALS OTHER THAN STYRENE, TO TEMPERATURES NOT ABOVE +10* C. IN THE PRESENCE OF AN AMOUNT OF ALUMINUM CHLORIDE ONLY SLIGHTLY IN EXCESS OF THAT REQUIRED TO INITIATE THE REACTION WHEREBY THE ISOBUTYLENE IS COPOLYMERIZED WTIH THE STYRENE TO THE SUBSTANTIAL EXCLUSION OF THE BUTENE-1, BUTENE-2, AND BUTADIENE. 